In commit ba97548686 `--with-termlib` was added to produce a
`libtinfo.a` file that nano then required. However, this causes ncurses
to build with _only_ screen-pointer ext funcs: e.g.
`reset_prog_mode_sp` exists, but `reset_prog_mode` does not.
By switching to `--enable-term-driver`, all functions are properly
exported again and the nano port compiles and runs just fine. :^)